Imprint apparatus and article manufacturing method

ABSTRACT

An imprint apparatus includes: a dispenser configured to dispense an imprint material to the imprint region; and a controller configured to control the imprint process so that a pattern is formed in a first imprint region, located upstream of a second imprint region with respect to a gas flow between the dispenser and the substrate, earlier than in the second imprint region.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an imprint apparatus and an articlemanufacturing method.

2. Description of the Related Art

As the demand for micropatterning of semiconductor devices increases, amicrofabrication technique of molding an uncured resin (uncuredmaterial) on a substrate using a mold to form a resin pattern on thesubstrate has received attention, in addition to a conventionalphotolithography technique. This technique is also called an imprinttechnique and can form a fine structure in the order of several nm onthe substrate. A photocuring method is one example of the imprinttechnique. In an imprint apparatus which adopts the photocuring method,first, an ultraviolet curing resin (UV curing resin) (to be simplyreferred to as a “resin” hereinafter) is dispensed to a shot region(imprint region) on the substrate (wafer). For example, an inkjet methodor the like is used as a dispensing method. Next, this resin (uncuredresin) is molded using the mold. Then, a mold is released after theresin is cured by ultraviolet irradiation, thereby forming the resinpattern on the substrate.

In this imprint apparatus, a pattern is formed (to be referred to as“imprinted” hereinafter) to a plurality of imprint regions in order froman adjacent imprint region first. However, the next adjacent imprintregion is influenced by heat or the like from the imprint region wherethe imprint process has been performed immediately before. There may bea case in which, for example, magnification correction of the nextadjacent imprint region cannot be performed accurately because theimprint region where the imprint process has been performed immediatelybefore and its peripheral substrate thermally expand or contract due tothe influences of heat of ultraviolet irradiation and the temperature ofthe mold during a pattern formation process. To solve this, for example,Japanese Patent Laid-Open No. 2009-065135 discloses a method ofpreventing two imprint regions where the imprint process is performedsuccessively from being adjacent to each other, thereby reducing athermal influence.

In the imprint apparatus, when dispensing the resin to the imprintregion on the substrate by the inkjet method, a part of the resin maybecome a foggy fine droplet (mist) and be scattered in the adjacentimprint regions. In this case, a pattern defect may occur in the imprintregion where the imprint process has been performed before.

SUMMARY OF THE INVENTION

The present invention provides, for example, an imprint apparatusadvantageous in reduction of a pattern defect thereby.

The present invention in its one aspect provides an imprint apparatusfor performing an imprint process of forming a pattern in an imprintregion on a substrate, the apparatus comprising: a dispenser configuredto dispense an imprint material to the imprint region; and a controllerconfigured to control the imprint process so that a pattern is formed ina first imprint region, located upstream of a second imprint region withrespect to a gas flow between the dispenser and the substrate, earlierthan in the second imprint region.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing an imprint apparatus according to the firstembodiment;

FIG. 2 is a view showing imprint regions and the order of an imprintprocess;

FIG. 3 is a view showing an imprint apparatus according to the secondembodiment; and

FIGS. 4A and 4B are views showing imprint regions and the order of animprint process according to the third embodiment.

DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present invention will be described in detail belowwith reference to the accompanying drawings.

First Embodiment

FIG. 1 shows an imprint apparatus according to the first embodiment ofthe present invention. An imprint apparatus 1 transfers a concavo-convexpattern of a mold 10 onto a substrate (wafer) 2 serving as a targetsubstrate used in a semiconductor device manufacturing process. Theimprint apparatus according to the first embodiment adopts a method ofcuring a resin with light when transferring the concavo-convex patternof the mold 10. As shown in FIG. 1, an axis parallel to a direction inwhich the mold 10 is irradiated with ultraviolet rays is set to theZ-axis, and the X-axis and the Y-axis are defined in a directionperpendicular to the Z-axis.

The imprint apparatus 1 includes a substrate stage 3 which holds thesubstrate 2, a mold holding unit 11 which holds the mold 10, acontroller 20, a dispenser 12, and a generator 31 which generates a gasflow 30. The substrate 2 is a substrate to be processed. For example, asingle-crystal silicon wafer, an SOI (Silicon on Insulator) wafer, orthe like is used for the substrate 2. The dispenser 12 dispenses animprint material serving as a molding member on the surface of thesubstrate 2 to be processed. An ultraviolet curing resin can be used asthe imprint material. A concavo-convex pattern to be transferred to theimprint material is formed to have a three-dimensional shape on thesurface of the mold 10 having a rectangle peripheral portion and facingthe substrate 2. A material which transmits ultraviolet rays such asquartz is used for the mold 10.

The mold holding unit 11 holds and fixes the mold 10, and imprints theconcavo-convex pattern of the mold 10 onto the substrate 2. The moldholding unit 11 includes a mold holding mechanism, a mold shapecorrecting mechanism, and a mold stage (all of which are not shown). Themold holding mechanism holds and fixes the mold 10 by a vacuum suctionpad. The mold holding mechanism is mechanically held by the mold stage.The mold stage is a driving system configured to position the spacingbetween the substrate 2 and the mold 10 when transferring theconcavo-convex pattern of the mold 10 onto the substrate 2, and isdriven in the Z-axis direction. The mold stage is required to performhighly accurate positioning when transferring the three-dimensionalpattern. Therefore, the mold stage may be formed by a plurality ofdriving systems such as a coarse driving system (device) and a finedriving system (device). Furthermore, the mold stage may have a positionadjustment function not only in the Z-axis direction but also in theX-axis direction, the Y-axis direction, or the θ direction (rotationaldirection around the Z-axis), and a tilt function of correcting the tiltof the mold 10. The mold shape correcting mechanism can correct theshape of the mold 10 by applying a force or a deformation to the sidesurface of the mold 10.

The substrate stage 3 is a driving system which is driven in the X-axisdirection and the Y-axis direction to correct (align) the translationshift between the substrate 2 and the mold 10. The driving system of thesubstrate stage 3 in the X-axis direction and the Y-axis direction mayalso be formed by the plurality of driving systems such as the coarsedriving system and the fine driving system. Furthermore, the substratestage 3 may have a driving system configured to perform a positionadjustment in the Z-axis direction, the position adjustment function inthe θ direction (rotational direction around the Z-axis) of thesubstrate 2, and a tilt function of correcting the tilt of the substrate2. The substrate stage 3 mechanically holds the substrate 2 by thevacuum suction pad.

The dispenser 12 dispenses the imprint material onto the substrate 2.The dispenser 12 includes a nozzle (not shown) which dispenses theimprint material and dispenses the imprint material from the nozzle ontothe substrate 2. It is known that when the dispenser 12 dispenses theimprint material, a droplet to land on the substrate 2 and a foggy finedroplet (mist) separated from the droplet are generated from thedispensed imprint material. The dispensing amount of the imprintmaterial can be determined based on, for example, the thickness of thenecessary imprint material or the density of the pattern to betransferred. A dispensing destination region is a shot region (imprintregion) serving as a target of the imprint process immediately afterdispensing. The controller 20 controls the operation, the adjustment,and the like of each component of the imprint apparatus 1. In the firstembodiment, the controller 20 specifically controls dispensing of theimprint material by the dispenser 12 and driving of the substrate stage3.

A clean chamber 7 stores the imprint apparatus 1. The clean chamber 7includes the generator 31 which generates the gas flow 30, a chemicalfilter (not shown), and a particle filter (not shown). A fan (supplydevice) 31 a draws in air in an atmosphere where the clean chamber 7 isplaced, a chemical substance and dust slightly contained in the drawnair are removed with the chemical filter and the particle filter, andthen clean air is supplied from an air blowing port (not shown) to aspace inside the clean chamber 7.

The generator 31 generates the gas flow 30 inside the imprint apparatus1 in order to exhaust heat, dust, and the like generated from theimprint apparatus 1. The generator 31 may aim to generate the gas flow30 between the dispenser 12 and the substrate stage 3. The generator 31can include a recovery device (vacuum generation mechanism) 31 b whichrecovers a gas and the supply device (fan) 31 a which supplies the gas.A vacuum pump can be used as the vacuum generation mechanism 31 b. Thevacuum generation mechanism 31 b may be arranged inside the cleanchamber 7. If the vacuum generation mechanism 31 b is arranged outsidethe clean chamber 7, an exhaust port can be arranged inside the cleanchamber 7 and connected to the vacuum generation mechanism 31 b arrangedoutside the clean chamber 7 using a duct or the like. Note that thearrangement position of the vacuum generation mechanism 31 b is notlimited to a position shown in FIG. 1, but may be arranged between thedispenser 12 and the mold 10. The gas flow 30 does not change itsdirection but can be fixed in a predetermined direction so as not toprevent the imprint material dispensed from the dispenser 12 from beinguniformly dispensed onto the substrate 2.

Additionally, the imprint apparatus 1 includes a substrate conveyingunit (device) configured to convey the substrate 2 onto the substratestage 3, a mold conveying unit configured to convey the mold 10 to themold holding unit 11, and an irradiation unit (device) configured toirradiate the mold 10 with the ultraviolet rays in the imprint process.The imprint apparatus 1 also includes a base surface plate 4 configuredto hold the substrate stage 3, a bridge surface plate 6 configured tohold the mold holding unit 11, and a column 5 configured to support thebridge surface plate 6.

A imprint method according to the first embodiment will now be describedwith reference to FIG. 2. FIG. 2 shows the order of performing, by theimprint apparatus 1 shown in FIG. 1, the imprint process on theplurality of imprint regions arranged on the substrate 2. As shown inFIG. 2, the axis perpendicular to the surface of the substrate 2 isdefined as the Z-axis, and axes parallel to the surface of the substrate2 are defined as the X-axis and the Y-axis. Each imprint region 50represents a unit region where the imprint material is dispensed ontothe substrate 2 and the mold 10 is brought into contact with thedispensed imprint material, thereby performing the imprint process offorming the pattern. As shown in FIG. 2, the imprint regions 50 areregularly arranged on a plurality of rows and a plurality of columns onthe substrate 2. In the first embodiment, the imprint regions arearranged on the plurality of rows and the plurality of arrays on thesubstrate 2. However, the imprint regions may only be arranged in thedirection of the plurality of rows.

The gas flow 30 is oriented in the X-axis direction, as indicated by anarrow. Assume that in FIG. 2, the upstream (weather side) of the gasflow 30 is on the left side and the downstream (lee side) is on theright side. According to the first embodiment, the imprint process isperformed for each row. That is, patterns are formed sequentially in theplurality of imprint regions belonging to one row and arranged along thegas flow 30. In the plurality of imprint regions on each row, theimprint process is performed in order from the imprint region on theweather side (left side of FIG. 2) of the gas flow 30 to the imprintregion on the lee side (right side of FIG. 2), and sequentially in theX-axis direction, as shown by the same broken-line arrow. Once theimprint region on the most lee side (rightmost side of FIG. 2) on thesame row is reached to complete the imprint process, the row is changedin the Y-axis direction, and the imprint process is sequentiallyperformed again on the plurality of imprint regions on the changed rowfrom the weather side (left side of FIG. 2) to the lee side (right sideof FIG. 2). The aforementioned controller 20 shown in FIG. 1 determinesthis order of the imprint process based on information about thedirection of the gas flow 30.

Second Embodiment

An imprint apparatus 1 according to the second embodiment of the presentinvention will now be described with reference to FIG. 3. In FIG. 3, adescription on similar portions to those in FIG. 1 will be omitted. Acontroller 20 in the imprint apparatus 1 according to the secondembodiment includes a gas-flow speed controller 32 which controls thespeed change in a gas flow 30 generated by a generator 31. The gas-flowspeed controller 32 outputs a command value for determining the speed ofthe gas flow 30 to a change mechanism (not shown) in the generator 31capable of changing the speed of the gas flow 30. The change mechanismcan use a butterfly valve which blocks the flow of the gas flow 30, apulse motor configured to control the degree of opening of the butterflyvalve, and the like. Alternatively, if a fan is used as the generator31, the change mechanism may use, for example, an inverter configured tochange the rotation speed of the fan.

The overspeed of the gas flow 30 generated by the generator 31 poses aproblem. That is, if the speed of the gas flow 30 is too high, even adroplet is flowed greatly into the gas flow 30 together with the mist ofan imprint material dispensed from a dispenser 12, making it difficultto land the droplet in an intended portion on a substrate 2 and makingit impossible to achieve uniform dispensing. As a result, accuratepattern formation may be impeded in the imprint apparatus 1.

According to the second embodiment, the gas-flow speed controller 32controls the speed of the gas flow 30, thereby making it possible toinhibit the droplet of the imprint material from being flowed into thegas flow 30 as much as possible and adjust a range where the mist of theimprint material is scattered. The range where the mist is scattered canbe limited to the imprint region of an imprint-process target and itsadjacent imprint region on the lee side. The speed of the gas flow 30can be adjusted and changed as needed based on, for example, the amountof the imprint material dropped when dispensing, uniformity whendispensing the imprint material onto the substrate 2, and the scatteringdistance of the mist of the imprint material in the lee-side directionof the gas flow 30, all of which are defined in a recipe.

Third Embodiment

An imprint method according to the third embodiment of the presentinvention will now be described with reference to FIGS. 4A and 4B. FIGS.4A and 4B show the order of performing an imprint process on a pluralityof imprint regions on a substrate 2. The order in FIGS. 4A and 4B ischanged from that shown in FIG. 2. In the first embodiment shown in FIG.2, the imprint process is performed for each row in the direction of thegas flow 30 and in the plurality of imprint regions on one row, theimprint process is performed in order from the imprint region on theweather side to the imprint region on the lee side. On the other hand,in the third embodiment, the imprint process is performed for eachcolumn in the imprint regions in the direction (Y direction)perpendicular to the direction of a gas flow 30, as shown in FIGS. 4Aand 4B. In the third embodiment, the imprint process is performed inorder, out of the plurality of columns, from the column on the weatherside to the column on the lee side. The advancing direction of theplurality of imprint regions arranged in the Y direction on one columnmay always be the same direction (for example, the + direction) alongthe Y-axis, as shown in FIG. 4A. Alternatively, the advancing directionof the imprint regions where patterns are formed sequentially may beopposite to each other between two adjacent columns, as shown in FIG.4B. The mist of the imprint material generated when dispensing theimprint material to the imprint regions where the imprint process isperformed is scattered in the imprint region where the imprint processhas not been performed, but is not scattered in the imprint region wherethe imprint process has already been performed. It is therefore possibleto prevent pattern defect occurrence owing to adhesion of the mist tothe pattern formed after performing the imprint process.

Other Embodiments

In the first to the third embodiments, the direction of the gas flow 30is not changed but fixed. However, the direction of a gas flow 30 may bechanged. In this case, however, a controller 20 needs to change theorder of an imprint process in accordance with the change in thedirection of the gas flow 30. The controller 20 can also change thedirection of the gas flow 30 in accordance with changing the order ofimprint regions where the imprint process is performed.

[Article Manufacturing Method]

An article manufacturing method according to an embodiment of thepresent invention is suitable for manufacturing an article, for example,a microdevice such as a semiconductor device or an element having amicrostructure. The manufacturing method includes a step of forming apattern on a substrate using an imprint apparatus 1. This manufacturingmethod can further include other known steps (oxidation, deposition,vapor deposition, doping, planarization, etching, resist peeling,dicing, bonding, packaging, and the like) of processing the substrate onwhich the pattern has been formed. The article manufacturing methodaccording to this embodiment is advantageous in at least one of theperformance, the quality, the productivity, and the production cost ofthe article, as compared to a conventional method.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2014-119889, filed Jun. 10, 2014, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An imprint apparatus for performing an imprintprocess of forming a pattern in an imprint region on a substrate, theapparatus comprising: a dispenser configured to dispense an imprintmaterial to the imprint region; and a controller configured to controlthe imprint process so that a pattern is formed in a first imprintregion, located upstream of a second imprint region with respect to agas flow between the dispenser and the substrate, earlier than in thesecond imprint region.
 2. The apparatus according to claim 1, whereinthe controller is configured to control the imprint process so that thepattern is formed sequentially in each of a plurality of imprint regionson the substrate arranged along the gas flow.
 3. The apparatus accordingto claim 2, wherein the controller is configured to control the imprintprocess so that the pattern is formed sequentially in each of aplurality of imprint regions in a first column, located upstream of aplurality of imprint regions in a second column with respect to the gasflow, earlier than in each of the plurality of imprint regions in thesecond column.
 4. The apparatus according to claim 3, wherein advancingdirections of the imprint process are opposite to each other between thefirst and second columns adjacent to each other.
 5. The apparatusaccording to claim 1, further comprising a generator configured togenerate the gas flow, wherein the controller is configured to controlthe generator so that a direction of the gas flow changes with respectto each row including a plurality of imprint regions for each of whichthe imprint process is performed sequentially.
 6. The apparatusaccording to claim 1, further comprising a generator configured togenerate the gas flow, wherein the generator includes a supply deviceconfigured to supply a gas associated with the gas flow.
 7. Theapparatus according to claim 1, further comprising a generatorconfigured to generate the gas flow, wherein the generator includes arecovery device configured to recover a gas associated with the gasflow.
 8. The apparatus according to claim 1, further comprising agenerator configured to generate the gas flow, wherein the controller isconfigured to control the generator so that a rate of the gas flow ischanged.
 9. The apparatus according to claim 8, wherein the controlleris configured to control the generator so that the rate is changed basedon a recipe for the imprint process.
 10. A method of manufacturing anarticle, the method comprising steps of: forming a pattern on asubstrate using an imprint apparatus; and processing the substrate, onwhich the pattern has been formed, to manufacture the article, whereinthe imprint apparatus performs an imprint process of forming the patternin an imprint region on the substrate, and includes: a dispenserconfigured to dispense an imprint material to the imprint region; and acontroller configured to control the imprint process so that a patternis formed in a first imprint region, located upstream of a secondimprint region with respect to a gas flow between the dispenser and thesubstrate, earlier than in the second imprint region.
 11. An imprintapparatus for performing an imprint process of forming a pattern in animprint region on a substrate, the apparatus comprising: a dispenserconfigured to dispense an imprint material to the imprint region; and acontroller configured to control the imprint process so that the patternis not formed in a second imprint region, located downstream of a firstimprint region with respect to a gas flow between the dispenser and thesubstrate, earlier than in the first imprint region.
 12. An imprintapparatus for performing an imprint process of forming a pattern in animprint region on a substrate, the apparatus comprising: a dispenserconfigured to dispense an imprint material to the imprint region; and acontroller configured to control the imprint process so that the patternis not formed, with respect to each column of the imprint region, in asecond imprint region, located downstream of a first imprint region withrespect to a gas flow, earlier than in the first imprint region.
 13. Animprint apparatus for performing an imprint process of forming a patternin an imprint region on a substrate, the apparatus comprising: a supplyport configured to supply a gas flow along the substrate; a dispenserconfigured to dispense an imprint material to the imprint region; and acontroller configured to control the imprint process so that the patternis not formed, with respect to each column of the imprint region alongthe gas flow, in a second imprint region, farther from the supply portthan a first imprint region, earlier than in the first imprint region.14. An imprint apparatus for performing an imprint process of forming apattern in an imprint region on a substrate, the apparatus comprising:an exhaust port configured to exhaust a gas flow along the substrate; adispenser configured to dispense an imprint material to the imprintregion; and a controller configured to control the imprint process sothat the pattern is not formed, with respect to each column of theimprint region along the gas flow, in a second imprint region, closer tothe exhaust port than a first imprint region, earlier than in the firstimprint region.
 15. An imprint apparatus for performing an imprintprocess of forming a pattern in an imprint region on a substrate withrespect to each of a plurality of the imprint region on the substratesequentially, the apparatus comprising: a dispenser configured todispense an imprint material to the imprint regions; and a controllerconfigured to control the imprint process so that the pattern is notformed in a second imprint region, located downstream of a first imprintregion with respect to a gas flow between the dispenser and thesubstrate, earlier than in the first imprint region.
 16. A method ofmanufacturing an article, the method comprising steps of: forming apattern on a substrate using an imprint apparatus; and processing thesubstrate, on which the pattern has been formed, to manufacture thearticle, wherein the imprint apparatus performs an imprint process offorming the pattern in an imprint region on the substrate, and includes:a dispenser configured to dispense an imprint material to the imprintregion; and a controller configured to control the imprint process sothat the pattern is not formed in a second imprint region, locateddownstream of a first imprint region with respect to a gas flow betweenthe dispenser and the substrate, earlier than in the first imprintregion.
 17. A method of manufacturing an article, the method comprisingsteps of: forming a pattern on a substrate using an imprint apparatus;and processing the substrate, on which the pattern has been formed, tomanufacture the article, wherein the imprint apparatus performs animprint process of forming the pattern in an imprint region on thesubstrate, and includes: a dispenser configured to dispense an imprintmaterial to the imprint region; and a controller configured to controlthe imprint process so that the pattern is not formed, with respect toeach column of the imprint region, in a second imprint region, locateddownstream of a first imprint region with respect to a gas flow, earlierthan in the first imprint region.
 18. A method of manufacturing anarticle, the method comprising steps of: forming a pattern on asubstrate using an imprint apparatus; and processing the substrate, onwhich the pattern has been formed, to manufacture the article, whereinthe imprint apparatus performs an imprint process of forming the patternin an imprint region on the substrate, and includes: a supply portconfigured to supply a gas flow along the substrate; a dispenserconfigured to dispense an imprint material to the imprint region; and acontroller configured to control the imprint process so that the patternis not formed, with respect to each column of the imprint region alongthe gas flow, in a second imprint region, farther from the supply portthan a first imprint region, earlier than in the first imprint region.19. A method of manufacturing an article, the method comprising stepsof: forming a pattern on a substrate using an imprint apparatus; andprocessing the substrate, on which the pattern has been formed, tomanufacture the article, wherein the imprint apparatus performs animprint process of forming the pattern in an imprint region on thesubstrate, and includes: an exhaust port configured to exhaust a gasflow along the substrate; a dispenser configured to dispense an imprintmaterial to the imprint region; and a controller configured to controlthe imprint process so that the pattern is not formed, with respect toeach column of the imprint region along the gas flow, in a secondimprint region, closer to the exhaust port than a first imprint region,earlier than in the first imprint region.
 20. A method of manufacturingan article, the method comprising: forming a pattern on a substrateusing an imprint apparatus; and processing the substrate on which thepattern has been formed to manufacture the article, wherein the imprintapparatus performs an imprint process of forming the pattern in animprint region on the substrate with respect to each of a plurality ofthe imprint region on the substrate sequentially, and includes: adispenser configured to dispense an imprint material to the imprintregions; and a controller configured to control the imprint process sothat the pattern is not formed in a second imprint region, locateddownstream of a first imprint region with respect to a gas flow betweenthe dispenser and the substrate, earlier than in the first imprintregion.